Transporting audiences from the Jungle of Nool to the Circus McGurkus, the Cat in the Hat, our narrator, tells the story of Horton, an elephant who discovers a speck of dust containing tiny people called the Whos, including Jojo, a Who child, who gets in trouble for thinking too many "thinks." Horton's challenge is twofold — not only must he protect the Whos from a world of naysayers and dangers, but he must also guard an abandoned egg that's been left in his care by the irresponsible Mayzie La Bird.